Audio converter device and method for using the same

ABSTRACT

An audio converter device and a method for using the same. The audio converter device receives the digital audio data from a first device via a local area network. The audio converter device decompresses the digital audio data and converts the digital audio data into analog electrical data. The audio converter device transfers the analog electrical data to an audio playback device.

RELATED APPLICATIONS

This Application claims the benefit of and is a continuation of U.S.application Ser. No. 10/976,458, filed on Oct. 29, 2004 which, in turn,claims the benefit of U.S. application Ser. No. 09/945,018, filed onSep. 1, 2001, and U.S. Provisional Application No. 60/230,530, filed onSep. 1, 2000, each of which is hereby incorporated by reference in theirentirety.

FIELD OF THE INVENTION

The present invention relates generally to audio playback devices, andmore particularly, to an audio converter device to convert digital audiodata received from a computer system to analog electrical data to beplayed on an audio playback device.

BACKGROUND

The rapid buildup of telecommunications infrastructure combined withsubstantial investment in Internet-based businesses and technology hasbrought Internet connectivity to a large segment of the population.Recent market statistics show that a majority of households in the U.S.own at least one personal computer (PC), and a significant number ofthese PCs are connected to the Internet. Many households include two ormore PCs, as well as various PC productivity peripherals such asprinters, scanners, and the like. Decreases in the cost of PC componentssuch as microprocessors, hard disk drives, memory, and displays, havedriven the commoditization of PCs. Although the majority of householdPCs are connected to the Internet by dialup modem connections, broadbandconnectivity is being rapidly adopted, and is decreasing in price as avariety of technologies are introduced and compete in the marketplace. Alarge majority of households in the U.S. and Europe are viable for atleast one or more type of broadband connection, such as cable, DSL,optical networks, fixed wireless, or two-way satellite transmission.

A market for home networking technology has emerged, driven by the needto share an Internet connection between two or more PCs, and to connectall the PCs to productivity peripherals. There has been innovation inlocal area network (LAN) technology based on end-user desire forsimplicity and ease of installation. Installing Ethernet cable isimpractical for a majority of end-users, therefore a number ofno-new-wires technologies have been introduced. The Home PhonelineNetworking Association (HPNA) promotes networking products that turnexisting phone wiring in the home into an Ethernet physical layer.Adapters are required that allow each device to plug into any RJ-11phone jack in the home. The adapter modifies the signal from devices sothat it can be carried by the home phone lines. Existing HPNA productsprovide data-rates equivalent to 10base-T Ethernet, approximately 10Mbps. Networking technology that uses the AC power wiring in the home tocarry data signals has also appeared. Similar to HPNA devices, adaptersare required to convert data signals from devices into voltagefluctuations carried on to and off of the AC wires, allowing any ACoutlet to become a network interface. Although both HPNA and power linenetworking products are convenient to use because they require no newwires, the advantage of AC power line products over HPNA is that ACpower outlets are more ubiquitous than RJ-11 phone jacks.

Wireless radio-frequency (RF) LAN technology has also been introducedinto the home networking market. Theoretically, wireless technology isthe most convenient for the end user to install. There are currently twoprevalent standards for wireless networking, Institute of Electrical andElectronics Engineers (IEEE) 802.11b and HomeRF. Both of these systemsutilize the unlicensed 2.4 Ghz ISM band as the carrier frequency for thetransmission of data. Both of these technologies have effective rangesof approximately 150 feet in a typical household setting. IEEE 802.11bis a direct sequence spread spectrum technology. HomeRF is afrequency-hopping spread spectrum technology. Adapters that are RFtransceivers are required for each device to communicate on the network.In addition to utilizing Transmission Control Protocol/Internet Protocol(TCP/IP) protocols, IEEE 802.11b and HomeRF include additionalencryption and security protocol layers so that the user's devices havecontrolled access to data being sent through the LAN.

Due to market competition and the effect of Moore's Law, home networkingtechnology is greatly increasing in performance and availability, whiledecreasing in price. For example, the current data-rate roadmap showsHomeRF increasing from 10 Mbps to 20 Mbps, utilizing the 5 Ghz band. TheIEEE 802.11 technology roadmap shows the introduction of 802.11a at 54Mbps, also utilizing the 5 Ghz band. It is important to note that LANdata-rates are increasing much faster than wide-area data-rates, such asthe data-rates provided by “last mile” technologies including DSL,DOCSIS. Wireless wide area data-rates are also improving slowly. Currentdigital cellular technology provides less than 64 Kbps data-rates, withmost systems providing throughput in the 20 Kbps range.

The MP3 digital audio format is an audio encoding technology that allowsconsumers to further compress digital audio files such as those found onCompact Disks, to much smaller sizes with very little decrease in soundquality. The MP3 format is the audio layer of MPEG-2 digital audio andvideo compression and transmission standard. For example, the MP3 formatallows for compression of audio content to approximately 1 million bytesper minute of audio, at near Compact Disk quality. This capability,combined with a decrease in the cost of flash memory, a type ofnon-volatile silicon-based mass memory, has made it possible to developportable digital audio playback devices. These are devices that aresignificantly smaller than portable CD players because they contain nomoving parts, only flash memory, a microprocessor for decoding MP3compressed audio content, and batteries. However, the cost per bit ofaudio content with portable digital audio playback devices is still veryhigh because of the high cost of flash memory. The typical portabledigital audio playback device includes enough flash memory to storeabout one CD's worth of digital music. The result is that the user isburdened with having to continually manually change the music files inthe device by plugging the device into the PC and operating a userinterface, if they want to listen to a wide range of music.

PC-based MP3 software players have been created that provide aconvenient graphical user interface and software decoding of MP3 files.Some technology allows users to play MP3 files on their PC, using anexisting sound card with external speakers. However, to listen to MP3sthe user must interface with the PC, using a mouse and keyboard, andmust be nearby the PC sound output equipment.

The smaller size of MP3 encoded audio files has also enabled these filesto be shared by users across the Internet, since the transfer of thesefiles takes an acceptable amount of time. Internet-based digital musicaccess and distribution service businesses have appeared that providevarious means for users to gain access to digital audio files.

In addition to music, many other types of audio content are nowavailable in digital format, such as spoken-word content, news,commentary, and educational content. Digital files containing audiorecordings of books being read aloud are available for download directlyfrom their website.

At the same time, there is a very large installed base of stereo systemsin households throughout the world. The majority of these systems arecapable of producing high fidelity audio if the audio inputs into thestereo system are of high quality.

What is needed is a system that allows users to play all of the digitalcontent that is stored on their PC, on their existing audio equipment.This system should include an audio content management system, andshould allow the user to control and manipulate the content that isstored on the PC, at the stereo system.

This system should also provide the ability to stream audio from sourcesbeyond the PC on the Internet. There should be a seamless interface thatallows user to manage both locally cached content and Internet streams.

SUMMARY

An audio converter device and a method for using the same are provided.In one embodiment, the audio converter device receives the digital audiodata from a first device via a local area network. The audio converterdevice decompresses the digital audio data and converts the digitalaudio data into analog electrical data. The audio converter devicetransfers the analog electrical data to an audio playback device.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood more fully from the detaileddescription given below and from the accompanying drawings of variousembodiments of the invention, which, however, should not be taken tolimit the invention to the specific embodiments, but are for explanationand understanding only:

FIG. 1 shows a schematic of one embodiment of the digital streamingaudio system hardware components;

FIG. 2 shows an isometric view of one embodiment of a digital audioconverter;

FIG. 3 shows an isometric exploded view of one embodiment of a digitalaudio converter;

FIG. 4 shows a block diagram of one embodiment of a digital audioconverter hardware components;

FIG. 5 shows a block diagram of one embodiment of the digital streamingaudio system software components;

FIG. 6 shows an isometric view of one embodiment of a digital audioconverter remote control;

FIG. 7 shows one embodiment of a PC desktop with the console and mediamanager GUI;

FIG. 8 shows one embodiment of a PC desktop with the mini-browser opento a content portal;

FIG. 9 shows one embodiment of a PC desktop with the media manager GUIopen with a dialog box;

FIG. 10 shows a flowchart of one embodiment of the GUI at digital audioconverter;

FIG. 11 shows one embodiment of a tag sequence flowchart;

FIG. 12 shows a schematic of one embodiment of a digital audio converterwith alarm clock function;

FIG. 13 shows an isometric view of one embodiment of the alarm clockcontroller;

FIG. 14 shows a schematic of one embodiment of a digital streaming audiosystem incorporating a PDA with an attached wireless LAN adapter modulewhich functions as the system controller and, or player device; and

FIG. 15 shows an isometric view of one embodiment of the PDA removedfrom the LAN adapter.

DETAILED DESCRIPTION

An audio converter device and a method for using the same are described.In the following description, for purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present invention. It will be apparent, however, toone skilled in the art that the present invention can be practicedwithout these specific details. In other instances, well-knownstructures and devices are shown in block diagram form in order to avoidobscuring the present invention.

A set of definitions is provided below to clarify the present invention.

Definitions

The Internet is used interchangeably with the term web or worldwide web.Both of these are defined as the worldwide network of PCs, servers, andother devices.

Broadband connection is defined as a communications network in which thefrequency bandwidth can be divided and shared by multiple simultaneoussignals. A broadband connection to the Internet typically providesminimum upstream and downstream data-rates of approximately 200K or morebits per second. There are many different types of broadband connectionsincluding DSL, cable modems, and fixed and mobile wireless connections.

A Data Over Cable System Interface Specification (DOCSIS) modem is anindustry standard type of cable modem that is used to provide broadbandaccess to the Internet 8 over a coaxial cable physical layer that isalso used for the delivery of cable TV signals (CATV).

A Digital Subscriber Line (DSL) modem is also an industry standard typeof modem that is used to provide broadband access to the Internet, butover conventional copper phone lines (local loops).

The term gateway, used interchangeably with broadband gateway, isdefined as an integral modem and router, and may include hubfunctionality. The modem function is used to change voltage fluctuationson an input carrier line (a DSL line input or a cable TV input) intodigital data.

Routers are devices that connect one distinct network to another bypassing only certain IP addresses that are targeted for specificnetworks. Hubs allow one network signal input to be split and thus sentto many devices.

Gateway storage peripheral is defined as an add-on storage device withprocessing power, an operating system, and a software application thatmanages the downloading and storage of data. An example scenario for theuse of a gateway storage peripheral is a system where a user has aDOCSIS modem and would like to add an always-on storage capability. Thegateway storage peripheral is connected to the DOCSIS modem via a USBport or an Ethernet port in the DOCSIS modem. A gateway storageperipheral in combination with a DOCSIS modem or any type of broadbandmodem is considered a storage gateway system. A PC that is always lefton and connected to an always-on gateway with a DSL or broadband cableconnection is considered a storage gateway system.

The term “message” is defined as information that is sent digitally fromone computing device to another for various purposes. The term “content”is used to mean the information contained in digital files or streams.For example, content may be entertainment or news, or audio files in MP3format. “Data” is used to mean information such as digital schedulecontents, responses from devices sent back through the system, ordigital messages and email. “Content” and “data” are sometimes usedinterchangeably. “Client devices” are those devices that are not fullyfunctional without a host device such as a personal computer.

Local Area Network (LAN) is defined as a network structure that includestwo or more devices that can communicate with other devices utilizing ashared communication infrastructure, including wired networktechnologies, such as Ethernet, or wireless network technologies such asInstitute of Electrical and Electronics Engineers (IEEE) 802.11b orHomeRF technology. Wireless LAN technology such as EEE 802.11b andHomeRF are based on the unlicensed 2.4 Ghz ISM (Industrial, Scientific,and Medical) frequency band and are well known the telecommunicationsand LAN industries. These networking technologies utilize TransmissionControl Protocol/Internet 8 Protocols (TCP/IP) protocols. A LANtypically constitutes a group of interconnected devices that share acommon geographic location and are typically grouped together as asubnet. A local network, for example, would be a home network whereseveral computers and other smart devices would be digitally connectedfor the purpose of transferring content and data, controlling eachother, sharing programming, or presenting data and content to a user.

Codec (Compression/Decompression algorithm) is a software applicationthat is used to decode (uncompress) encoded (compressed) media files orstreams. Most content is stored and sent in a compressed format so thatthe content files are smaller and thus take up less storage space anduse less bandwidth when being transferred via the Internet. The contentis then decoded at the playback device. For example, MP3 audio files areencoded and must be decoded by a microprocessor running the codec inorder for the audio content to be presented to the user in an analogformat.

HTTP is Hyper-text transfer protocol, the protocol used by Web browsersand Web servers to transfer files, such as text and graphic files.

Data-rate is defined as the data throughput of a telecommunicationssystem or technology, and is measured in a quantity of bits per second,such as millions of bits per second (Mbps).

Overview of Operation

The fundamental operation of the digital streaming audio system involvesLAN transmission of digital audio files 116 from a local source that isa personal computer (PC) 24, to a digital audio converter 32 thatreceives the stream and converts it into a signal that can be input intoa conventional stereo system 40. Referring now to FIG. 1, the keyhardware components in the system are PC 24 connected to the Internet 8.The PC 24 is also functionally connected via a USB connection 64 to awireless radio frequency (RF) LAN access point 28, such that digitalcontent from PC 24 is transmitted to nodes on the LAN. Digital audioconverter 32, shown in FIG. 2, is located within communication range ofthe wireless LAN access point 28, and is connected to a conventionalstereo receiver 44 via the right and left RCA jack inputs. Stereoreceiver 44 is part of a stereo system 40 that includes a left speaker48 and a right speaker 48. FIG. 4 is a block diagram of a portion of thedigital streaming audio system including digital audio converter 32 andthe stereo system 40, showing how left analog output 156 and rightanalog output 160 included in digital audio converter 32 are connectedrespectively to the left line input 78 and right line input 82 onexisting stereo receiver 44. Digital audio converter 32 also includes aremote control 52 that communicates with digital audio converter 32 viaan IR communication link 38. Stereo system 40 functions in theconventional way, pre-amplifying and amplifying the audio signals anddelivering them to the left speaker 48 and the right speaker 48.

The function of the PC 24 in the digital streaming audio system is toacquire, store, manage, and serve digital audio content to digital audioconverter 32. The PC 24 gains access to digital audio content severalways. In one embodiment the PC 24 is also connected to the Internet 8via a broadband cable modem 16. Thus the PC 24 has access via contentservices to both downloadable digital audio files 116 such as MP3formatted content files, as well as digital audio streams from Internet8 servers. For example, some radio stations provide access to theirprogramming via digital audio streams.

In other embodiments, PC 24 is connected to Internet 8 through a dial-upmodem connection to an ISP, or Digital Subscriber Line (DSL), or a fixedwireless broadband connection.

Wireless LAN transceivers are capable of sending and receiving datausing radio frequencies via a wireless data transfer protocol.Technology for such a LAN is currently available and includes theSymphony wireless networking access point provided by Proxim, Inc. ofSunnyvale Calif. LAN systems such as this are based on RF modulationcentered on the 2.4 GHz frequency band. Such LANs have a practical rangeof approximately 150 feet and are capable of reaching most areas in anaverage sized house where a stereo system 40 and digital audio converter32 are located. In another embodiment, the wireless LAN access point 28is a PCI card that is located internal to the PC 24, with an externalantenna. In another embodiment, the wireless LAN communication link 6 isprovided using IEEE 802.11b protocols.

The function of digital audio converter 32 is to receive digital audiostreams sent from the PC 24, decode and de-compress the digital audio inreal time, convert it from a digital format into a analog electricalsignals, specifically a left analog audio signal and a right analogaudio signal. Through the use of digital audio converter 32, the stereosystem 40 is the output device for digital audio content that wasinitially stored on the PC 24 or on the Internet 8.

Digital audio converter 32 includes an LCD 50 that is used to displaydata relevant to the audio content being played, such as track titles.In one embodiment, digital audio converter 32 includes one set ofcontrol buttons on the remote control 52, which attaches onto to theenclosure 60 of digital audio converter 32. In another embodiment,control buttons are included on both an IR remote control 52 andintegral to the main enclosure 60. The purpose of the control buttons isto provide a user interface for controlling the digital streaming audiosystem, as well as a tag button 620 used to maintain a record of certainaudio content on the PC 24 for later use, and control of other features.

The control buttons include the conventional controls that are found onaudio playback devices including power on/off button 600; track forwardbutton 608 and track backward button 612—for advancing through andselecting tracks for playback; menu button 652; play/pause button604—for starting and pausing (stopping at point in the middle of aplayback of an audio track); stop button 616—for stopping playback ofaudio content; tag button 620—for triggering the transmission ofinformation about a currently playing digital audio content back throughthe system for delivery to the end user on a website or for delivery tothe content creator or content originator; user-defined button 624—abutton that may be associated with a variety of functions as selected bythe user using the audio playback device setup GUI. A four-waynavigation control 644 including navigate up button 628, navigate downbutton 632, navigate left button 640, and navigate right button 636. Aselect button is included in the center of the four-way navigationcontrol 644. These control buttons are also shown on a remote control 52in FIG. 6.

Mechanical Description

Referring now to FIGS. 2 and 3, one embodiment of digital audioconverter 32 includes a three-piece plastic injection-molded enclosure60 including a top housing 54, a bottom housing 58, and a front bezel66. Internal hardware also includes LCD 50 that contains an integralbacklight so that the LCD 50 may be read in low light, a powerregulation sub-system 30, an infrared (IR) receiver 34 and relatedcircuitry, and a printed circuit board (PCB) 70 that contains theelectronic components that constitute the functional data-manipulatingaspect of digital audio converter 32. In one embodiment, the wirelessLAN transceiver 36 antenna 26 is located internal to the digital audioconverter 32 housing as shown in FIG. 3. The entire assembly is heldtogether with threaded fasteners.

The construction of the remote control 52 is a typical two-piece plasticshell construction as shown in FIG. 6. Internal hardware includes aninfrared (IR) transceiver and batteries, as well as a printed circuitboard that contains the electronic components that constitute thefunctional data-manipulating aspect of digital audio converter 32. Inone embodiment, the remote control 52 is removably attached to theenclosure 60.

Electrical Description

FIG. 4 shows a block diagram of the electrical components in digitalaudio converter 32. PCB electrically connects components including amicroprocessor 10 with dynamic memory (DRAM) 14, programmable (flash)memory 18 for storage of control firmware 100 when power is turned off,a power regulation sub-system 30, and a plurality of input/outputterminals including an Ethernet port and a right analog output 160 and aleft analog output 156. A wireless LAN transceiver 36 with associatedantenna 26 is functionally connected to the PCB. PCB also functionallyconnects an infra-red (IR) control sub-system 34 for processing IRcommands from the remote control 52. Digital audio converter 32 alsoincludes a digital-to-analog converter (DAC) 22 for converting theuncompressed digital information into analog signals that are presentedat the standard left analog output 156 and right analog output 160 RCAconnectors. A display driving sub-system 53 is also included forpresenting text and graphical information to the user. Microprocessor 10in combination with DRAM memory 14 executes instructions from its realtime operating system 96 and control firmware 100.

In another embodiment, digital audio converter 32 includes a terrestrialbroadcast tuner subsystem for tuning local AM and FM broadcast radio.

In another embodiment, power to the stereo system 40 is supplied via aswitched power line from the converter box so that the system has thecapability of turning the stereo on and off. The on/off function iscontrolled via software on the PC 24 or through the remote control 52,so that when the digital audio converter 32 is powered on, the stereosystem 40 is also automatically powered on.

System Software Description

FIG. 5 displays the relevant software components of the digitalstreaming audio system. In one embodiment, the software required on thePC 24 includes an operating system 72, such as the WindowsXP operatingsystem provided by Microsoft of Redmond, Wash. Wide area communicationsoftware 121 is also required for connecting to the Internet 8, which istypically provided as drivers in operating system 72. LAN communicationdrivers 92 are required for connecting the PC 24 to the LAN. Digitalaudio files 116 such as MP3 formatted files are stored on the hard diskdrive 68.

Software Module—System Control Application

The system control application 76 is software executing on PC 24 thatmanages communication and streaming from PC 24 to digital audioconverter 32. System control application 76 includes a server module 88that is a Java application. System control application 76 also includesa database module 80 that is written to or accessed by server module 88,and a graphical user interface (GUI) module 84, that provides a userinterface for setting up content to be streamed to digital audioconverter 32 and played on the stereo system 40. In one embodiment, theGUI module 84 is a native Windows 32-bit application.

In another embodiment, the GUI module 84 is available on a web page,implemented as HTML and Java Server Pages (JSP).

The GUI module 84 provides a user interface that is used to organizeaudio content into lists. The lists that are created using the GUImodule 84 at PC 24 are accessible at digital audio converter 32 via theuse of control buttons on remote control 52 and visual output on LCD 50.

FIG. 7 shows a PC desktop 200 with the media manager GUI 208 running.The console 204 is a GUI element that appears when server module 88 isrunning. Console 204 shows icons for any devices that are activelycommunicating on the LAN. Digital audio converter icon 224 is shownpresent on console 204. Media manager GUI 208 is launched from digitalaudio converter icon 224 on console 204 by clicking on digital audioconverter icon 224 on console 204 with a mouse.

The media manager GUI 208 features a three-level nested list structure.The three levels are labeled as channels 212, playlists 216, and tracks220. Channels 212 are lists of playlists 216, and playlists 216 arelists of tracks 220. Track 220 is a GUI representation of a locallycached digital audio file 116 or a digital audio stream from Internet 8.Channels 212 can be added by right-clicking with the mouse on thechannel bar 232. A menu is displayed that allows the user to create andlabel channel 212 by typing in text. Playlists 216 can be added tochannels 212 by right clicking on a channel 212 label and selecting theoption to add playlist 216. Playlists 216 can also be added to channels212 by left clicking with the mouse on the add playlist button 236.Tracks 220 can be added to playlists 216 by using the mouse to click onthe add track button 240. FIG. 9 shows the result of left clicking onadd track button 240. A conventional Windows dialog box 248 isdisplayed. The left side of dialog box 248 includes a navigation windowthat allows the user to navigate to any directory on local PC 34 or toany other PC that are accessible on the LAN.

Tracks 220 can also be added to playlists 216 by dragging and droppingan audio file icon from a window on the desktop, onto track 220 list.

Tracks 220 can also be added to playlists 216 by dragging and droppingtrack 220 icon from the music library 244. Music library 244 is a windowthat shows all of the digital audio files 116 stored on the local harddisk drive 68 that can be decoded by digital audio converter 32. Asoftware agent included in server module 88 of system controlapplication 76 searches hard disk drive 68 for compatible audio files,enters the names and locations of those files into database module 80,and places labels of the files in music library 244.

Audio content services are also available through online servicesaccessed through a browser interface. FIG. 8 shows a web-based contentselection guide 252 that provides the ability to make a playlist online.The online digital audio files associated with online playlist titles 99in the online playlist 122 are streamed to digital audio converter 32via PC 34 and wireless LAN communication link 6. Server module 88includes software that interfaces with the protocols of each onlineaudio service provider to allow online playlists 122 to be downloadedand transferred into database module 80. Thus, playlist structures andplaylist titles created online using the web-based content selectionguide 252 are available and can be interacted with by the user with theuser interface at digital audio converter 32.

Referring now to FIG. 7, media manager GUI also includes a PC audiodevice control interface 260, which includes the conventional controlsfor controlling an audio player device. PC audio device controlinterface 260 allow the user to control digital audio converter remotelyfrom PC 24. Using a preference setting, the audio sound playing that iscontrolled by PC audio device control interface 260 can be directed tothe local PC 24 speakers. In other words, the digital audio file 116that is selected to be played can be decoded locally at PC 24 and playedon PC 24 speakers.

Device Software—Digital Audio Converter Operating System

In one embodiment digital audio converter 32 operates using VxWorks, areal-time operating system 96 provided by WindRiver Systems. Digitalaudio converter 32 control firmware 100 is a software application thatis run on real time operating system 96 and manages the processing ofmessages from the IR sub-system 34, communication with system controlapplication 76 via LAN 6, stream buffering, and decoding of digitalaudio.

Device Software—Device GUI

A GUI is provided at digital audio converter 32. The GUI is operatedusing remote control 52 and LCD 50. FIG. 10 shows a graphical userinterface flow chart to describe the user interface structure. The threelevels of content organization provided by the media manager GUI 208correspond to three display lines on digital audio converter 32 LCD 50.The display lines are manipulated by using the four-way navigationcontrol 644 on remote control 52. Referring now to FIG. 10, each screen(1-9) is described below:

1. Initial state of digital audio converter 32 is shown. The top line oftext shows the current channel, the second line of text shows thecurrent playlist, and the third line of text shows the current track.Digital audio converter 32 status icon 256 shows the filled squaresymbol, which is the conventional symbol for a playback system that isin “stop” mode, i.e., nothing is playing. The channel level is depictedas the current channel by being graphically reversed (text is white withblack background).

2. This screen shows the result of activating the right navigationbutton. The channel level label changes to “channel 2”. The labels atthe playlist level and the tracks level also update to reflect the newitems in “channel 2”.

3. This screen shows the result of activating the down navigationbutton. The highlight moves from the channel level to the playlistlevel.

4. This screen shows the result of next activating the right navigationbutton. The playlist level changes to “playlist2”, the next playlistorganized under “channel 2”. The track level text also updates toreflect the actual first track included in “track 1” under “playlist 2”.

5. This screen shows the result of next activating the play/pause buttonon the remote control 52. “Track 1” begins to play. Status icon 256changes from a black square to a right-pointing triangle.

6. This screen shows the result of next activating the next track buttonon digital audio converter 32 remote control 52. “Track 3” begins toplay.

7. This screen shows the result of next activating the play/pause buttonwhile a track is playing. The track stops playing and status icon 256 isthe “pause” icon.

8. This screen shot shows the result of a few different actions. First,the play/pause button was activated, thus “Track 3” begins to play whereit left off when the play/pause button was activated. Next, the rightnavigation button is activated once. The track line advances to show thenext track, or “Track 4” in “Playlist 2”. “Track 3” continues to play.This feature allows the user to browse through thechannel/playlist/track list structure while continuing to listen to acurrently playing track.

9. This screen shows the result if no other buttons are activated forsix seconds. The display reverts back to display the channel, playlist,and track that are currently being played.

The corresponding other buttons, such as the up navigation and leftnavigation buttons move the highlight to the corresponding label.

Device Software—CODECs

In one embodiment, digital audio converter 32 includes the FraunhoferCODEC 104, licensed for use by Thomson Electronics for decoding thedigital audio file that is streamed to it from PC 34. CODEC 104 is anexecutable file stored in memory, launched by control firmware 100,executed by real time operating system 96 running on digital audioconverter 32. Digital audio converter 32 may store multiple CODECs inmemory 18 for decoding variously formatted digital audio files 116 thatmay be selected by the user. For example, the WindowsMedia CODEC,provided by Microsoft may be stored in memory 18 at digital audioconverter 32.

Software Functions—Communication/Message Processing

The communication and streaming functions of the system will now bedescribed. A user uses remote control 52 to control the function ofdigital audio converter 32. Button activations on remote control 52result in IR pulse codes that are received by the IR receiver sub-system34 in digital audio converter 32. These IR pulse codes are deciphered bythe computer sub-system in digital audio converter 32 and are convertedinto messages that are interpreted by the control firmware 100 runningon digital audio converter 32 to invoke action at digital audioconverter 32. Other IR pulses codes from remote control 52 are processedby control firmware 100 and are converted into XML-based messages andsent via HTTP requests to PC 24 via the wireless LAN. These messages areinterpreted by server module 88 running on PC 24 and specific actionsare initiated.

For example, assume that digital audio converter 32 is currently in playmode, that is, a first digital audio file 116 is currently beingstreamed to digital audio converter 32, decoded, and correspondinganalog signals are being produced at the analog outputs. The useractivates forward one track button 608 and IR pulse code is generated bythe IR sub-system 34 in remote control 52. IR pulse code is received bythe IR sub-system 34 in digital audio converter 32 and is interpreted bycontrol firmware 100 running on digital audio converter 32 as a “forwardone track” command. XML message expressing the “forward one track”command is sent by microprocessor 10 to system control application 76 onPC 24. The “forward one track” XML message is transmitted by wirelessLAN transceiver 36 via the LAN, by an HTTP request, to wireless LANaccess point 28 connected to PC 24. The HTTP request containing the“forward one track” message is received by server module 88, whichaccesses the next track name and location of the file associated withthe next track name, in database 80. The text string for the track nameis expressed in an XML message and is sent to back to digital audioconverter 32. This text string is interpreted by control firmware 100running at digital audio converter 32 and the text string is thendisplayed on LCD 50.

The preferred embodiment also enables the streaming of digital audiofiles 116 with a buffer management function that controls the flow ofportions of the digital audio file 116 from PC 24 into a local DRAMmemory 14 of digital audio converter 32. The buffer management functioninsures that the local DRAM memory 14 buffer is filled as the contentsof DRAM 14 are decoded by microprocessor 10 executing the CODEC 104.

Other Features—Downloadable Firmware and CODECs

An aspect of control firmware 100 on digital audio converter 32 is theability to receive and install new CODECs 104 via LAN communication link6. Non-volatile flash memory 18 in digital audio converter 32 ispartitioned into two sectors, flash memory sector A and flash memorysector B. A control bit determines the flash memory sector from whichoperating system 96 and control firmware 100 is loaded. In an initialstate, operating system version A and control firmware version A areloaded into DRAM 14 upon boot of digital audio converter 32. Digitalaudio converter 32 is functional. New versions of the software,operating system B and control firmware B are sent to digital audioconverter 32 via wireless LAN communication link. Operating system B andcontrol firmware B are then written into flash memory sector B. Achecksum is provided to insure that the exact image of the software hasbeen successfully written into flash. If the checksum at digital audioconverter 32 matches the control checksum, the control bit is changed tocause the system to boot from flash sector B. Either a device rebootcommand is initiated from the server module 88, or a reboot is initiatedat digital audio converter 32. Operating system B and control firmware Bare then loaded into DRAM. Digital audio converter 32 operates with newversions of the software. The next new version of software is loadedinto flash sector A. Each successive revision of software is loaded intothe flash sector A or flash sector B that is not the current bootableflash memory sector.

Other Features—Tagging

Because LAN technology is a two-way interconnection technology,responses from digital audio converter, in one embodiment, may be sentback through the digital streaming audio system and processed andpresented to the user and other interested entities at both PC 24 and onthe web. FIG. 6 shows tag button 120 on remote control 52. FIG. 11 is aflow chart of the tagging sequence. During the playing of digital audiofiles 116, activation of tag button 620 by the user results in atransmission of an XML message back through LAN informing system controlapplication 76 server module 88 that tag button 620 was activated.Server module 88 then compiles and transmits tag XML message to a tagstorage and processing server. The information in tag XML message mayinclude but is not limited to: metadata or meta-tags (ID3 data) includedin the file or stream (characters or images); the file name if contentis a file; the URL or IP address of the stream if content 116 is astream; time; date; and user identifier.

The transmission of tag XML message can have different results. Theinformation in the message may be formatted as a readable text messageand presented to a user on a personal tag aggregation web page. In thisscenario, the user has signed up with an account and receives a passwordfor entry into protected tag aggregation web page.

For the tagging function, the server module 88 should have access toaccurate time and date information. Server module 88 includes a functionthat accesses a server on Internet 8 where accurate time and date datais available, and these quantities are stored locally by server module88 in system control application 76 database module 80.

Other Features—User-Defined Button

A user programmable user-defined button 624 is provided on remotecontrol 52. The function of user-defined button 624 can be changed basedon a menu of items available via GUI module 84. For example, auser-defined menu may be accessible via a left mouse click on digitalaudio converter icon 224 on console 204. The left mouse click on digitalaudio converter icon 224 causes a preference menu to appear. Somepossible functions for user-defined button 624 are: delete currentlyplaying track from the current playlist; purchase the currentlystreaming digital audio file 116 (if it is a sample digital audio file);shuffle the tracks in the existing playlist; repeat the currentplaylist, if the active level is the playlist level; repeat the currentchannel if the active level is a channel.

Use of the System

The PC 24 downloads several digital audio files 116 through the Internet8 during the night and stores them on hard drive 68. At some time duringthe day, the user builds a playlist 216 of the digital audio files 116to be played on his/her stereo system 40. Using digital audio converter32 and remote control 52, the user requests to listen to the digitalaudio files 116. This information is relayed to the PC 24. The PC 24then sends the audio content to the stereo system 40 where it is played.The user continues to manipulate the playlist 216 through the use ofremote control 52 and tags certain songs that he/she finds appealing.The user later returns to the PC 24 and builds a new music playlist 216from the newly downloaded digital audio files 116.

Alternative Embodiments

FIG. 12 shows an embodiment of the invention used to perform thefunctions of an alarm clock for use with a stereo system 40. The systemincludes an alarm clock controller 132 such as the one illustrated inFIG. 13. The alarm clock controller 132 includes a wireless LANtransceiver and the functional components required to allow the alarmclock remote controller 132 to operate as a node on the wireless LAN.The user can input a wake-up time into a PC 24 using a GUI or on alarmclock controller 132, which is sent, via the LAN communication link 6,to digital audio converter 32. Digital audio converter 32 may include aswitched AC power conversion function that is used to switch on thestereo receiver 44 at the specified time in order to wake up a personsleeping in the room. The audio content that is played on the stereo atthe time of wake-up can be pre-selected according to the userspreferences. The alarm clock controller includes several buttons used toperform such functions as inputting a wake up time, tagging a web page,or turning the stereo off (snooze button). The alarm clock controller132 includes a display 312 and several control buttons 308 used toperform such functions as inputting a wake up time and tagging digitalaudio.

In an alternative embodiment, the alarm clock controller includes an IRtransceiver and other necessary components for establishing an IRcommunication link to digital audio converter 32. The IR communicationlink to digital audio converter 32 is used here instead of a wirelessLAN communication link to the PC 24. The alarm clock controller moduleretains the same functionality as previously described, but mustcommunicate with the system via digital audio converter 32.

In a further embodiment, digital audio converter 32 remote control 52functions as the alarm clock controller. The user can use the remotecontrol 52 to set the wake-up time for the stereo to turn on and/or usethe remote control 52 to switch the stereo off (snooze function). Theuser-defined button can be programmed by the user to function as asnooze button.

FIG. 14 shows an embodiment of the invention where a PDA 144 docked witha wireless LAN adapter 148 is used as an enhanced controller and/orplayer used with the system. FIG. 15 shows the PDA 144 removed from thewireless LAN adapter 148. The PDA 144 is used as the system controllerand is used to manage the audio content that is delivered to the stereoby manipulating software on the PC 24 through a wireless LANcommunication link to the PC 24. For example, the user can create oredit a playlist that is stored in the database module 80 on the PC 24,by using a browser GUI on the PDA 144. The PDA 144 can be similarly usedto perform functions such as volume control, song skip, and pause.Furthermore, earphones can be connected to the wireless LAN adapter 148through an audio out jack and the wireless LAN adapter 148 can be usedto play audio content stored on the PC 24. An audio data stream from thePC 24 is sent to the wireless LAN adapter 148, where it is decoded andconverted into an analog audio signal that is sent to earphones. In thiseffect, the wireless LAN adapter 148 is functioning as digital audioconverter 32, but has the added advantage of being portable. A customuser interface application on the PDA 144 is used as the user interface.

The PDAs that are included in this system are PDAs that are currentlysold as standalone PDA devices such as the Palm III, made by Palm Inc.FIG. 13 shows a generic PDA. By docking a PDA with the wireless LANadapter, the PDA essentially becomes a node in the LAN established bythe wireless LAN access point 28 connected to the PC 24. Through the useof the wireless LAN adapter, in conjunction with software on the PDA 144and software on the PC 24, the PDA can send data to and receive datafrom the PC 24. FIG. 14 shows a PDA docked with a wireless LAN adapter148. Electrical contacts on the rear end of the PDA make contact withelectrical contacts 608 on the wireless LAN adapter 148 in order toestablish a data communication link. There is a printed circuit boardthat contains the electronic components that constitute the functionaldata-manipulating aspect of wireless LAN adapter. Batteries are includedto supply power to the wireless LAN adapter 148. The wireless LANadapter further includes an audio output jack. In the preferredembodiment, the antenna is located internal to the PDA, mounted to theprinted circuit board.

The PDA can also be incorporated into the system by using onboard IRcapabilities. In this scenario, the PDA would communicate with thesystem via an IR communication link to the Wireless LAN-to-audioconverter and would be used to perform similar functions to those of theremote control 52 described in one embodiment.

In another embodiment, a PDA is used that contains the processing powerto decode and convert digital audio files. An example of such a PDA isthe Compaq iPaq, manufactured by Compaq Computer. In this case, awireless LAN Compact Flash transceiver card can be added to theCompactFlash card slot on the iPaq. A streaming player softwareapplication is also installed on the PDA that allows the PDA tointerconnect to they system control application 76 on the PC 24 as if itwere digital audio converter 32. A GUI on the PDA allows the user toselect playlists and control the streaming of digital audio files to thePDA.

Home PC 24 to Stereo Player System has several permutations that havenot yet been explicitly mentioned, but are implied: the system can bewholly controlled through the PC 24 and can be used without the use of aremote control 52 and/or a PDA; digital audio converter 32 can beinternally incorporated into a new stereo device; the buttons on digitalaudio converter 32 can be regarded as optional; the switched power lineon digital audio converter 32 can be regarded as optional; the wirelessLAN adapter can be internally incorporated into a new PDA device; theaudio in/out jack on the HRF Adapter Sled Module and its associatedfunctions can be regarded as optional; HRF antennas can be locatedinternal or external to digital audio converter 32 s they serve.

In another embodiment the LAN connection between the PC 24 and device isEthernet. In a different embodiment, the LAN connection between the PC24 and digital audio converter 32 is an networking technology that usesthe existing phone lines in the home as the physical layer. In yetanother embodiment, the LAN connection between the PC 24 and digitalaudio converter 32 is a networking technology that uses the existing ACpowerlines in the home as the physical layer.

In another embodiment, a residential storage gateway or a storagegateway system is used in place of or in addition to the PC 24 to runthe system control application 76, connect to the Internet 8, and storefile based content. In another embodiment, the system controlapplication 76 including server module 88, database module 80, and GUImodule 84 can be run on a set-top box that includes a cable modem and ahard disk drive and can perform the same functions.

An audio converter device and a method for using the same have beendescribed. Although the present invention is described herein withreference to specific embodiments, many modifications and variationstherein will readily occur to those with ordinary skill in the art.Accordingly, all such variations and modifications are included withinthe intended scope of the present invention as defined by the followingclaims.

1. A system comprising: a server device having an associated contentmanagement system by which a user creates a play list for accessing oneor more of a plurality of digital media files accessible to the serverdevice; and a client device in communication via a local area networkwith the server device, the client device having an associated displayfor displaying a representation of at least a portion of the play listreceived from the server device and having a user interface for allowinga user to interact with the displayed play list and to cause the clientdevice to transmit via the local area network to the server device arequest to initiate playing of one or more digital media filesrepresented on the displayed play list; wherein the client devicefurther comprises a volatile memory buffer to store portions of adigital media file requested to be played when transmitted to the clientdevice from the server device via the local area network; amicroprocessor to convert portions of the digital media file as storedin the volatile memory buffer into a format usable by a playback system;and a buffer management function to control flow of portions of thedigital media file requested to be played from the server device to theclient device to ensure that the volatile memory buffer is filled asportions of the digital media file already received from the serverdevice and stored in the volatile memory buffer are being converted bythe microprocessor.
 2. The system as recited in claim 1, wherein theclient device comprises a portable device.
 3. The system as recited inclaim 2, wherein the portable device comprises the playback system. 4.The system as recited in claim 3, wherein the portable device comprisesa personal digital assistant.
 5. The system as recited in claim 1,wherein the display comprises a portable device.
 6. The system asrecited in claim 5, wherein the portable device comprises a personaldigital assistant.
 7. The system as recited in claim 6, wherein thepersonal digital assistant is dockable with the client device.
 8. Thesystem as recited in claim 7, wherein the client device comprises theplayback device.
 9. The system as recited in claim 1, wherein thedisplay is operatively attached to the client device.